[PATCH 1/9] x86/intel_rdt: Fix MBA parsing callback

From: Fenghua Yu <fenghua.yu@intel.com>
To: "Thomas Gleixner" <tglx@linutronix.de>,
	"Ingo Molnar" <mingo@redhat.com>, "H Peter Anvin" <hpa@zytor.com>,
	"Tony Luck" <tony.luck@intel.com>
Cc: "Chatre, Reinette" <reinette.chatre@intel.com>,
	"Xiaochen Shen" <xiaochen.shen@intel.com>,
	"Chen Yu" <yu.c.chen@intel.com>,
	"linux-kernel" <linux-kernel@vger.kernel.org>,
	"x86" <x86@kernel.org>, "Fenghua Yu" <fenghua.yu@intel.com>
Subject: [PATCH 1/9] x86/intel_rdt: Fix MBA parsing callback
Date: Fri, 14 Sep 2018 13:32:01 -0700	[thread overview]
Message-ID: <1536957129-70380-2-git-send-email-fenghua.yu@intel.com> (raw)
In-Reply-To: <1536957129-70380-1-git-send-email-fenghua.yu@intel.com>

From: Xiaochen Shen <xiaochen.shen@intel.com>

Each resource is associated with a parsing callback to parse the
data provided from user space when writing schemata file.

Commit 9ab9aa15c309 ("x86/intel_rdt: Ensure requested schemata
respects mode") changes the first parameter 'data' of parse_ctrlval()
from string to a pointer to a structure. parse_ctrlval() could point
to two functions parse_cbm() and parse_bw() and both of the
functions should be changed to take the different type of parameter
'data'. But the commit only changes parse_cbm(), not parse_bw().
Thus, parse_bw() takes wrong 'data' parameter and causes failure
of parsing MBA throttle value.

To fix the issue, parse_bw() should handle its first parameter as
right structure instead of a string.

Fixes: 9ab9aa15c309 ("x86/intel_rdt: Ensure requested schemata respects mode")

Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
---
 arch/x86/kernel/cpu/intel_rdt.h             |  2 +-
 arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c | 24 ++++++++++-----------
 2 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/arch/x86/kernel/cpu/intel_rdt.h b/arch/x86/kernel/cpu/intel_rdt.h
index 4e588f36228f..8c30772e37ed 100644
--- a/arch/x86/kernel/cpu/intel_rdt.h
+++ b/arch/x86/kernel/cpu/intel_rdt.h
@@ -432,7 +432,7 @@ struct rdt_resource {
 };
 
 int parse_cbm(void *_data, struct rdt_resource *r, struct rdt_domain *d);
-int parse_bw(void *_buf, struct rdt_resource *r,  struct rdt_domain *d);
+int parse_bw(void *_data, struct rdt_resource *r, struct rdt_domain *d);
 
 extern struct mutex rdtgroup_mutex;
 
diff --git a/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c b/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c
index af358ca05160..d427c86e7cd0 100644
--- a/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c
+++ b/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c
@@ -28,6 +28,11 @@
 #include <linux/slab.h>
 #include "intel_rdt.h"
 
+struct rdt_parse_data {
+	struct rdtgroup		*rdtgrp;
+	char			*buf;
+};
+
 /*
  * Check whether MBA bandwidth percentage value is correct. The value is
  * checked against the minimum and max bandwidth values specified by the
@@ -64,19 +69,19 @@ static bool bw_validate(char *buf, unsigned long *data, struct rdt_resource *r)
 	return true;
 }
 
-int parse_bw(void *_buf, struct rdt_resource *r, struct rdt_domain *d)
+int parse_bw(void *_data, struct rdt_resource *r, struct rdt_domain *d)
 {
-	unsigned long data;
-	char *buf = _buf;
+	struct rdt_parse_data *data = _data;
+	unsigned long bw_val;
 
 	if (d->have_new_ctrl) {
 		rdt_last_cmd_printf("duplicate domain %d\n", d->id);
 		return -EINVAL;
 	}
 
-	if (!bw_validate(buf, &data, r))
+	if (!bw_validate(data->buf, &bw_val, r))
 		return -EINVAL;
-	d->new_ctrl = data;
+	d->new_ctrl = bw_val;
 	d->have_new_ctrl = true;
 
 	return 0;
@@ -123,18 +128,13 @@ static bool cbm_validate(char *buf, u32 *data, struct rdt_resource *r)
 	return true;
 }
 
-struct rdt_cbm_parse_data {
-	struct rdtgroup		*rdtgrp;
-	char			*buf;
-};
-
 /*
  * Read one cache bit mask (hex). Check that it is valid for the current
  * resource type.
  */
 int parse_cbm(void *_data, struct rdt_resource *r, struct rdt_domain *d)
 {
-	struct rdt_cbm_parse_data *data = _data;
+	struct rdt_parse_data *data = _data;
 	struct rdtgroup *rdtgrp = data->rdtgrp;
 	u32 cbm_val;
 
@@ -195,7 +195,7 @@ int parse_cbm(void *_data, struct rdt_resource *r, struct rdt_domain *d)
 static int parse_line(char *line, struct rdt_resource *r,
 		      struct rdtgroup *rdtgrp)
 {
-	struct rdt_cbm_parse_data data;
+	struct rdt_parse_data data;
 	char *dom = NULL, *id;
 	struct rdt_domain *d;
 	unsigned long dom_id;
-- 
2.19.0

